'When a German communicates you listen,' Arsène Wenger said of Arsenal's Per Mertesacker after the win against Swansea. Photograph: Clive Mason/Getty Images

This occasion will be remembered with a little warmth by Arsenal. Arsène Wenger's team have already had enough of eventful days such as the 8-2 defeat at Old Trafford in their previous match. So it was that the team could take a shine to this mundane game that brought a first win of the season in the Premier League.

Arsenal have a better excuse than most for looking as if the new campaign took them by surprise. They were not in command of the transfer market timing that saw them lose Cesc Fábregas and Samir Nasri so late in the summer. The lineup on Saturday was intended to restore calm as much as collect points. While that task was completed, it has to be borne in mind that Swansea are yet to score in the Premier League.

Wenger was full of approval for Swansea, even if that was an indirect way to make excuses for his own side's inconsequentiality. He spoke of the danger they carry on the flanks but then drew a painful analogy. "They remind me of Blackpool last year," Wenger said. "They play in an audacious way, not restricted at all, with a good technical level. But their next home game [against West Bromwich Albion on Saturday] will certainly be very important." Blackpool, of course, were relegated.

It is still too soon to live in dread. Swansea beat Arsenal home and away during the 1981-82 season and even now this sort of fixture can still be hard-fought. The decisive moment itself was a matter of aberration rather than inspiration, with the goalkeeper Michel Vorm tossing a throw-out against the heels of his right-back, Angel Rangel. Andrey Arshavin tucked the loose ball home from an angle in the 40th minute.

"I felt for Vorm at the other end," said the Arsenal goalkeeper, Wojciech Szczesny. "It can happen. He must be gutted. If you do that kind of mistake then you want to lose 3-0, not 1-0." Szczesny himself is full of confidence after pulling off a string of saves in Poland's 2-2 home draw with Germany in the friendly last week and then being termed world-class by Oliver Kahn, one of the most renowned goalkeepers of modern times.

Team-mates at the Emirates have not generally had cause to feel so sure of themselves in the wake of that pummelling by Manchester United. Szczesny looked unaffected and is adamant that Arsenal can be title contenders. With the immediate challenge of the Champions League game at Borussia Dortmund on Tuesday in mind, Wenger was happy to talk about the centre‑half Per Mertesacker, newly arrived from Werder Bremen for £8m. The manager is not above resorting to cliche when it is so reassuring. "He's calm and he talks and he communicates," Wenger said. "When a German communicates you listen."

The notion of enhanced authority in Arsenal ranks was sporadically called into doubt and, at the very end of the match, Danny Graham lifted an effort over the bar from close range. It was Graham, too, whose shot had been saved by Szczesny in the eighth minute. Both teams also hit the woodwork. There was purpose to Swansea, despite the fact that the manager, Brendan Rodgers, had gone to Northern Ireland following the death of his father. Rodgers's assistant Colin Pascoe was in charge at the Emirates.

This was an inherently difficult match for Arsenal. Wenger's overhaul of the squad had to be conducted at the last moment and he did not risk changing the team radically. Mikel Arteta, tidy in a deep-lying role in midfield, was joined by one other debutant in the starting lineup, Mertesacker, although Yossi Benayoun would have his first appearance as a substitute.

The meeting with Dortmund will be more demanding and three Polish players in the Bundesliga club's squad, Lukasz Piszczek, Robert Lewandowski and Jakub Blaszczykowski, have attempted to unsettle the Arsenal goalkeeper. "They've been taking the mickey out of it [the 8-2 result] but they can't get into my head," Szczesny said. "I will be focused." Even so, the match can surely bear no resemblance to a run-of the-mill engagement with Swansea.

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